A cipher which uses a different encryption key every time, as long as the message. The key is XOR'ed with the message to render the cipher text which can then be XOR'ed with the same key to get the plain text.

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10
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4answers
2k views

Is the one-time-pad a secure system according to modern definitions?

Occasionally I hear people say that one-time pads are "useless" or even "broken". "modern cryptography knows more security definitions, under some of which the one-time pad is completely ...
0
votes
2answers
110 views

Sending the next one-time pad key in this one-time pad message? [duplicate]

I am doing a research project on cryptography next year, and I'm really new to cryptography. This isn't some really advanced thing or anything, and I'm just trying to come up with something basic. ...
0
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1answer
104 views

Is this adaptation of one-time-pad still secure?

Having shared a pad of length double the length of your anticipated message, splitting it into x and y. Then using x to encrypt the message, and using y twice to encrypt the next pad, would that be ...
-1
votes
4answers
157 views

One time pad in CBC mode?

I have been searching about if it is more secure to use CBC mode in OTP but I can't find anywhere where people have sad that it is more secure. Question: Is CBC mode in OTP more secure? Because I ...
3
votes
2answers
170 views

Does the One Time Pad rely on confusion or diffusion?

From what I could research, XORing a random key adds confusion. But I do not undertand the rationale for that classification. Shannon's confusion is supposed to obscure the relationship between the ...
0
votes
1answer
122 views

Is there an asymmetric One-Time-Pad? [duplicate]

Is there something like a perfect asymmetric crypto-algo? Is there proof that there must be one or not. From a logical point of view it seems to be possible to design such algorithm if your keysize is ...
2
votes
2answers
535 views

Is One Time Pad considered Chosen-Plaintext Attack Secure?

If we're considering Chosen-Plaintext Attack setting, then the adversary has access to the Encryption Oracle right, and we know that OTP is only considered secure if we use the key only once. How ...
-3
votes
1answer
120 views

XOR = Best encryption? [duplicate]

If you have a TRULY random key (in binary) and you have a text (in binary) that you want to encrypt. Can you simple XOR the key and the text? Is that secure? How secure?
1
vote
1answer
117 views

How to decrypt unusual Many Time Pad

How does one decrypt the many time pad: ($R$ is a random string, $C$ is ciphertext, $P$ is plaintext) $R_0 \oplus R_1 = C_0$ $R_2 \oplus R_1 = C_1$ $P_0 \oplus R_1 = C_2$ assuming that $R_n$ are ...
1
vote
2answers
241 views

Why are there no OTP ciphers?

We all know the OTP is unbreakable and we all love the OTP (judging by the amount of question on this site). The strength of the OTP is not that it is unable to find a word without the key but you ...